Artemisia ludoviciana
Gen. N. Amer. Pl. 2: 143. 1818.
Perennials, 20–80 (rarely to 120 in desert washes) cm, aromatic (rhizomatous). Stems relatively few to relatively numerous, erect, gray-green, simple or widely branched, hairy. Leaves cauline, uniformly gray-green, green, or white, or bicolor (white and green); blades linear to broadly elliptic, 1.5–11 × 0.5–4 cm, entire or lobed to relatively deeply pinnatifid, faces hairy. Heads (erect to nodding, peduncles 0 or 2–5 mm) in congested to open (widely branched) arrays. Involucres campanulate or turbinate, (1–) 2–4 (–5) × 2–5 (–8) mm. Phyllaries (gray-green), lanceolate to ovate or obovate (margins narrowly hyaline), densely tomentose. Florets: pistillate 5–12; bisexual 6–45; corollas yellow, sometimes red-tinged, 1.5–2.8 mm, glabrous. Cypselae ellipsoid ca. 0.5 mm, (obscurely nerved) glabrous. 2n = 18, 36, 54.
Distribution
Alta., B.C., Man., N.B., Ont., P.E.I., Que., Sask., Ala., Ariz., Ark., Calif., Colo., Conn., Del., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Mass., Md., Mich., Minn., Miss., Mo., Mont., N.C., N.Dak., N.H., N.J., N.Mex., N.Y., Nebr., Nev., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Va., Vt., Wash., Wis., Wyo., Mexico
Discussion
Subspecies ca. 7 (6 in the flora).
Selected References
None.
Lower Taxa
Key
| 1 | Leaves usually relatively deeply lobed (1/3+ widths, nearly to midrib, proximal leaves sometimes entire); involucres 3–8 mm diam.; mountain meadows and slopes | > 2 |
| 1 | Leaves entire or relatively shallowly lobed (lobes to 1/3 widths); involucres 2–3(–4) mm diam.; desert valleys and mountains | > 3 |
| 2 | Involucres 4–5 × 4–8 mm | Artemisia ludoviciana subsp. candicans |
| 2 | Involucres 3–4 × 3–5 mm | Artemisia ludoviciana subsp. incompta |
| 3 | Heads in paniculiform arrays (4–)8–30 cm diam.; leaves mostly 1.5–2 cm | Artemisia ludoviciana subsp. albula |
| 3 | Heads in paniculiform or racemiform arrays 1–6 cm diam.; leaves 1.5–11 cm | > 4 |
| 4 | Leaf margins plane | Artemisia ludoviciana subsp. ludoviciana |
| 4 | Leaf margins revolute | > 5 |
| 5 | Leaves bicolor (gray-green and bright green), margins mostly entire, abaxial faces glabrous | Artemisia ludoviciana subsp. redolens |
| 5 | Leaves gray-green, margins usually lobed, abaxial faces hairy | Artemisia ludoviciana subsp. mexicana |